Proteins - Primary + Secondary Structure Flashcards
Primary
What allows proteins to carry out different functions in organisms?
Every protein has a different shape
Primary
When a polypeptide is made, what determines the primary structure of the protein?
The order of the amino acids
Primary
What is the definition of the primary structure of a protein?
The sequence of amino acids
Primary
What are most polypeptide chains made up of?
Many hundreds of amino acids
Primary
What does the almost limitless number of combinations allow every protein to have?
A completely unique primary structure
Secondary
Polypeptide chains aren’t always straight.
What are the 2 main shapes they are found in?
a-helix
ß-pleated sheets
Secondary
Why do the polypeptide chains fold and coil into these shapes?
Due to the structure of the amino acids -
They all contain a -C=O group and a -NH group when bonded in a chain
Secondary
Why do you get hydrogen bonds between amino acids?
Because the hydrogen in -NH is slightly positive and the oxygen in the -C=O is slightly positive
Secondary
What keeps an a-helix stable?
The polypeptide chain coils with the hydrogen bond
Secondary
What do the ß-pleated sheets chains do?
Form a zig zag and fold over themselves
Secondary
Why is the secondary structure so stable when hydrogen bonds are weak?
Because hundreds of hydrogen bonds together become strong and can keep the secondary structure stable
Secondary
What is the definition of the secondary structure in a protein?
It is the curling or folding of the polypeptide chain into a-helices and ß-pleated sheets due to the formation of hydrogen bonds
